School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Key Laboratory of Pollution Treatment and Resource, China National Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan Province, China.
School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China.
J Hazard Mater. 2022 Feb 15;424(Pt A):127392. doi: 10.1016/j.jhazmat.2021.127392. Epub 2021 Sep 29.
Many studies have proved the impacts of nanoplastic pollution in freshwaters on aquatic organisms and ecosystems. To explore toxic mechanisms of nanoplastics on stream functioning, we conducted a microcosm experiment to investigate the effects of polystyrene nanoparticles (PS NPs, 1-100 μg L) on the process of leaf litter decomposition mediated by the microbial community. The chronic exposure to PS NPs at 1 and 100 μg L caused significant decreases in leaf litter decomposition and nutrient (carbon and nitrogen) releases. During the ecological process, some extracellular enzymes (i.e., β-glucosidase, glycine-aminopeptidase, and phenol oxidase) rather than fungal biomass were suppressed. Besides, decreases in the relative abundance of Anguillospora and Setophaeosphaeria weakened their functions in leaf litter decomposition. Thus, the microcosm experiment showed that PS NPs inhibited stream leaf decomposition by modulating the microbial metabolic activity and fungal community structure. Overall, the results of this study provide evidence for the consequences of nanoplastic pollution on freshwater microbial community and stream ecosystem functioning, which is conducive to evaluate the potential risks of nanoplastics in aquatic environments.
许多研究已经证明了淡水环境中纳米塑料污染对水生生物和生态系统的影响。为了探究纳米塑料对溪流功能的毒性机制，我们进行了一项微宇宙实验，以研究聚苯乙烯纳米颗粒（PS NPs，1-100μg/L）对微生物群落介导的落叶分解过程的影响。PS NPs 在 1 和 100μg/L 的慢性暴露会显著降低落叶分解和养分（碳和氮）的释放。在生态过程中，一些细胞外酶（即β-葡萄糖苷酶、甘氨酰-氨基肽酶和酚氧化酶）而非真菌生物量受到抑制。此外，Anguillospora 和 Setophaeosphaeria 的相对丰度降低削弱了它们在落叶分解中的作用。因此，微宇宙实验表明，PS NPs 通过调节微生物代谢活性和真菌群落结构来抑制溪流落叶分解。总的来说，这项研究的结果为纳米塑料污染对淡水微生物群落和溪流生态系统功能的影响提供了证据，有助于评估纳米塑料在水生环境中的潜在风险。
